133972621 has 4 divisors (see below), whose sum is σ = 134039932. Its totient is φ = 133905312.

The previous prime is 133972613. The next prime is 133972627. The reversal of 133972621 is 126279331.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 41139396 + 92833225 = 6414^2 + 9635^2 .

It is a cyclic number.

It is not a de Polignac number, because 133972621 - 2³ = 133972613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133972627) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30576 + ... + 34681.

It is an arithmetic number, because the mean of its divisors is an integer number (33509983).

Almost surely, 2^133972621 is an apocalyptic number.

It is an amenable number.

133972621 is a deficient number, since it is larger than the sum of its proper divisors (67311).

133972621 is an equidigital number, since it uses as much as digits as its factorization.

133972621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67310.

The product of its digits is 13608, while the sum is 34.

The square root of 133972621 is about 11574.6542496958. The cubic root of 133972621 is about 511.6881404171.

The spelling of 133972621 in words is "one hundred thirty-three million, nine hundred seventy-two thousand, six hundred twenty-one".